Actually the word “nostrils” is in all bible books that I have.
When checked online, I found several different versions. I am not sure if I was being fed with non-legitimate sources then. But just now, I re search again, I found the word “nostril” is consistent.
So I found this article, which include
a section Embriology of The Nose , which explains the timely development of the external and internal nose of fetus. Beginning as mere a swelling that appear during the fifth week of gestation that starts the formation of the fetus external nose and the nasal septum development also on the fifth week, but it begins to look like a nose on the 6.5 week.
https://emedicine.medscape.com/article/8372
Quote from article:
Beginning at 6.5 weeks, lateral nasal wall development occurs. The inferior concha appears above the palatine process. As the nasal cavity heightens, ectodermal folds appear in the ethmoid region and give rise to superior, middle, and inferior concha.
Anterior to these folds appear agger nasi cells and the uncinate process, future site of the bulla ethmoidalis and hiatus semilunaris. Paranasal sinuses develop as diverticula of the lateral nasal walls, extending into maxillary, ethmoid, frontal, and sphenoid bones. Their development concludes during puberty.
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